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排序方式: 共有8144条查询结果,搜索用时 15 毫秒
41.
Serial in vivo MR tracking of magnetically labeled neural spheres transplanted in chronic EAE mice. 总被引:5,自引:0,他引:5
Tamir Ben-Hur Ruud B van Heeswijk Ofira Einstein Michal Aharonowiz Rong Xue Emma E Frost Susumu Mori Benjamin E Reubinoff Jeff W M Bulte 《Magnetic resonance in medicine》2007,57(1):164-171
Neural stem cell (NSC) transplantation has been shown to attenuate the severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Central to the future success of NSC transplantation in MS is the ability of transplanted cells to migrate from the site of transplantation to relevant foci of disease. Using magnetically labeled mouse neurospheres and human embryonic stem cell (hESC)-derived neurospheres, we applied serial magnetic resonance imaging (MRI) to assess the biodynamics of transplanted cell migration in a chronic mouse EAE model. Magnetic labeling did not affect the in vitro and in vivo characteristics of cells as multipotential precursors. Cell migration occurred along white matter (WM) tracts (especially the corpus callosum (CC), fimbria, and internal capsule), predominantly early in the acute phase of disease, and in an asymmetric manner. The distance of cell migration correlated well with clinical severity of disease and the number of microglia in the WM tracts, supporting the notion that inflammatory signals promote transplanted cell migration. This study shows for the first time that hESC-derived neural precursors also respond to tissue signals in an MS model, similarly to rodent cells. The results are directly relevant for designing and optimizing cell therapies for MS, and achieving a better understanding of in vivo cell dynamics and cell-tissue interactions. 相似文献
42.
Hiroaki Shiba Takeyuki Misawa Susumu Kobayashi Tokuyasu Yokota Kyonsu Son Katsuhiko Yanaga 《Journal of gastrointestinal surgery》2007,11(4):549-551
A 41-year-old Chinese woman was admitted to our hospital with epigastric pain. Computed tomography detected a heterogeneous
enhancement tumor fed by the left gastroepiploic artery in the left lower quadrant and cholelithiasis. Excision of the tumor
in the greater omentum and cholecystectomy were performed laparoscopically. Histological findings confirmed a diagnosis of
hemangiopericytoma with low-grade malignancy. To our knowledge, hemangiopericytoma of the greater omentum is very rare, and
only 12 cases were reported in English literature. We report a case of hemangiopericytoma arising in the greater omentum and
review the literature. 相似文献
43.
In order to investigate the comparative fates of nivalenol (NIV) and 4-acetyl derivative of NIV (fusarenon-X, FX) in mice, 3H-FX or 3H-NIV was given p.o. to mice. Radioactivity was excreted mainly via the urine in mice given 3H-FX, but mainly via the feces in mice given 3H-NIV. The plasma radioactivity reached a peak at 30 or 60 min after the administration of 3H-FX or 3H-NIV, respectively. The plasma peak level was 5 times higher, and the area under curve (AUC) was 10 times higher, in 3H-FX-administered than 3H-NIV-administered mice. These findings clearly demonstrate that FX is absorbed from the gastrointestinal tract more rapidly and efficiently than NIV. The HPLC profile of radioactivity of acetonitrile extracts of urine and feces indicated that FX is rapidly metabolized to NIV after being absorbed from the gastrointestinal tract. In vitro incubation of tissue homogenates with 3H-FX demonstrated that the liver and kidney are the organs responsible for the FX-to-NIV conversion. Thus this study demonstrated that the higher oral toxicity of FX than NIV that has been observed in mice and rats is due to the efficient absorption of FX than NIV from the gastrointestinal tract, followed by its rapid conversion to NIV by the liver and kidney. 相似文献
44.
Yoshimi Otani Ichiro Yoshida Satoshi Ohki Motoi Kano Osamu Kawashima Masao Suzuki Yasushi Sato Toru Takahashi Akio Ohtaki Susumu Ishikawa Yasuo Morishita 《Surgery today》1997,27(9):812-815
Pulmonary aspergillosis associated with old tuberculosis is generally resistant to treatment. Thus, if patients are treated
only with conservative therapy, their condition continues to deteriorate due to repetitive hemoptysis, and may even become
critical. Surgical treatment is required for these patients; however, it is extremely difficult to resect the lesion due to
severe adhesions to the chest wall and vascular proliferation surrounding the lesion. We performed preoperative arterial embolization,
achieving good results in three patients with hemoptysis caused by pulmonary aspergillosis. The feeding arteries were embolized
using microcoils and/or gelatin sponges, and a lobectomy was safely carried out in all patients. We concluded that preoperative
arterial embolization is a safe and effective technique to prevent massive hemorrhage occurring at the time of surgery.
This work was presented at the 11th Annual Meeting of the Japanese Association for Chest Surgery, held in Kyoto, Japan, May
13–14, 1994 相似文献
45.
Analysis of T Cell Receptor Variability in Fresh Tumor-infiltrating Lymphocytes from Human Head and Neck Cancer 总被引:1,自引:1,他引:0
Kazuaki Chikamatsu Masao Eura Koji Nakano Yuichi Kanzaki Hiroaki Matsuoka Keisuke Masuyama Takeru Ishikawa 《Cancer science》1994,85(6):626-632
In this study, we analyzed T cell receptor (TCR) gene rearrangements in tumor-infiltrating lymphocytes (TIL) freshly obtained from 15 patients with head and neck cancer using the reversely transcribed polymerase chain reaction (RT-PCR) method. These TILs showed preferential expression of Vα10, Vα8 and Vα1, detected in 13 (87%), 11 (73%), and 9 cases (60%), respectively. The TCRVβ gene revealed diversity without preferential usage. The head and neck region is exposed to bacteria and viruses, so it is possible that the tumor site can become infected and accumulate T cells involved in infection and inflammation. Therefore, we also investigated TCR gene usage in T cells infiltrating in chronic sinusitis mucosa to address the question of whether the Vα1, Vα8, and Vα10 subfamilies are characteristic in TIL from squamous cell carcinoma of head and neck. TCR Vα10 gene usage was also the most common in Vα segment in T cells infiltrating the sinus mucosa, but Vα and Vα8 were not detected in the T cells in sinusitis. These results indicate that the Vα10 subfamily, the preferred T cell population in both TIL and T cells in inflammatory disease, might he involved mainly in inflammation or infection. On the other hand, Vα1 and Vα8 appear to be relatively specific populations for antitumor immunity in head and neck cancer. 相似文献
46.
Koichi Nishimura Takashi Hajiro Toru Oga Mitsuhiro Tsukino Susumu Sato Akihiko Ikeda 《The Journal of asthma》2005,41(2):141-146
Simple and concise measures for health status are desirable in clinical practice. The Asthma Bother Profile (ABP), which consists of 23 items, has been developed to assess how much asthma bothers patients. The Airways Questionnaire 20 (AQ20) is a simple instrument which consists of 20 items. The purpose of this study was to investigate how the ABP and AQ20 evaluate the health status of patients with asthma. A total of 166 patients with chronic asthma (age: 48 ± 16 yr, 77 males) completed pulmonary function testing, measurement of airway hyperresponsiveness, dyspnea rating, assessments of their anxiety and depression (HADS; Hospital Anxiety and Depression Scale), and assessments of their health status. The health status was assessed using the ABP, AQ20, the short-form 36 health survey questionnaire (SF-36), the Living With Asthma Questionnaire (LWAQ) and the Asthma Quality of Life Questionnaire (AQLQ). The Japanese version of the ABP included only 15 'bother' items out of the original 23 items due to cultural differences. The scores on the ABP were widely distributed, whereas the scores on the AQ20 were skewed towards the milder end of the scale. The ABP had a strong correlation with the Avoidance and Distress constructs on the LWAQ, and Anxiety and Depression on the HADS (Rs = 0.56 ∼ 0.79), and its strongest correlation with the General Health (Rs = - 0.64) scale among the 8 subscales on the SF-36. The AQ20 had a less significant correlation with the LWAQ, AQLQ, and SF-36 than the ABP. The ABP and AQ20 were short and simple to complete, and both measures could easily be used in clinical practice. The ABP can evaluate patients more specifically with respect to distress and bother than the AQ20. 相似文献
47.
Hiroko Sasahara Susumu Sueyoshi Toshiaki Tanaka Hiromasa Fujita Kazuo Shirouzu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(5):231-239
Objective: The purpose of this experimental study was to investigate whether aortic stent grafting can be applied to the treatment of
an esophageal cancer involving the thoracic aorta. Methods: The canine thoracic aorta was partially resected without aorta being clamped after emplacement of an endovascular stent graft.
Study I; The aortic whole layer of 1 cm in length and 1/4 of the circumference was resected and was covered by a free fascia
patch of the abdominal rectal muscle immediately after stent graft placement. Study II; The aortic adventitia and the outer
half of the media of the same size was resected on day 3, 7,14, 21, and on day 28, after the stent graft placement. The resected
portion was covered by the free fascia patch in half experimental dogs, and was uncovered in the others. Study III; The aortic
adventitia and the outer half of the media of 1 cm in length and 1/2 of the circumference was resected and was uncovered on
day 7 after stent graft placement. Histological examinations were performed on day 28 and at one year after aortic resection.
Results: The aortic wall could be resected in all cases with no complication, except in resection of 1/2 the circumference where the
aorta had become narrow. There was no difference in healing of the resected portion of the aorta between with and without
fascia covering. Conclusion: An aortic endovascular stent graft could be applied to surgery for an esophageal cancer involving the aorta. 相似文献
48.
49.
The anisotropy of the water diffusion tensor inside brain causes contrast in diffusion images, which depends on the relative orientation of the diffusion gradients and the subject. Because the trace of a tensor is invariant upon rotation, measurement of this trace can reduce the orientation effect. A family of imaging pulse sequences is presented in which the signal intensity is weighted by the trace of the diffusion tensor in a single scan. The methods are demonstrated for chicken gizzard in several orientations with respect to the gradient frame of reference, and for ischemic injury in cat brain after middle cerebral artery occlusion. The sensitivity of the techniques to the presence of background gradients is measured and discussed in detail. As a result, pulse sequences are suggested that provide reliable diffusion constants in both homogeneous and inhomogeneous magnetic fields. The efficiency of the techniques for clinical application is also evaluated. 相似文献
50.
Dr. Susumu Itoh MD Kazuhiro Marutani MD Shuichi Matsuo MD 《Digestive diseases and sciences》1992,37(8):1260-1267
We studied the histological and ultrastructural changes in the liver and alterations in the liver test results before, during, and after treatment with human interferon- from five patients with hepatitis B e antigen-positive chronic active hepatitis. A daily dose of 3×106 to 6×106 units of interferon- was given intravenously for four weeks. The total index of periportal and portal inflammation, intralobular degeneration, and focal necrosis before treatment was decreased significantly six months after treatment (P<0.05). Ultrastructurally, the structure of endoplasmic reticulum was irregularly shaped or fragmentally decreased during treatment, but these disappeared six or 12 months after treatment. Glycogen particles diminished greatly during treatment. The alanine aminotransferase concentrations in these patients increased during treatment. Serum albumin and cholinesterase levels decreased significantly at the fourth week of treatment (P<0.01) and at the third day (P<0.01) to the second week (P<0.05) of treatment, respectively. These results suggest that interferon- injures endoplasmic reticulum and glycogen areas and damages the cholinesterase activity in the early stage of treatment and protein synthesis in patients with hepatitis B e antigen-positive chronic active hepatitis. 相似文献